Prospective Epidemiological Surveillance Research Articles

Mental health, chronic and infectious conditions among pregnant persons in US state prisons and local jails 2016-2017.

Pregnant individuals in incarcerated settings have unique healthcare needs. Rates of mental health, infectious diseases, and chronic disease are higher among nonpregnant incarcerated women compared with those who are not, but the prevalence of these conditions among pregnant people in custody has not been documented. The objective of this study is to describe the prevalence of metabolic, infectious, and mental health conditions in pregnant people to identify the medical needs of high-risk pregnancies in US state prisons and local jails. This was a prospective epidemiologic surveillance of a convenience sample of state prisons (n = 20) and local jails (n = 3). We used purposive and snowball sampling to recruit a national sample of prisons and jails of a range of sizes and geographies. Reporters submitted to our study database monthly data on selected pregnancy comorbidities for 6 months between 2016 and 2017. Screening, diagnosis, and tracking of these conditions are derived from each facility's medical record and health care delivery systems. Of the 445 newly admitted pregnant people in prisons and 243 in jails, the most prevalent conditions were mental health conditions and hepatitis C. Specifically, 34.1% (n = 152) in prison and 23.5% (n = 57) in jail had a substance use disorder, and 27.4% (n = 122) of those in prison and 17.7% (n = 43) in jail had a psychiatric diagnosis. Finally, 20.2% (n = 91) in prison and 6.6% (n = 16) in jail had hepatitis C. This study demonstrates that chronic medical and mental health conditions are prevalent among pregnant people in US prisons and jails. However, significant variability in the reported number of cases of these conditions from state to state and between facility types implies a lack of or inadequate screening practices. These data indicate the need for comprehensive screening and appropriate care for the complex needs of pregnant incarcerated people.

Emergence and evolution of drug-resistant Mycobacterium tuberculosis in eastern China: A six-year prospective study

Understanding the emergence and evolution of drug resistance can inform public health intervention to combat tuberculosis (TB). In this prospective molecular epidemiological surveillance study from 2015 to 2021 in eastern China, we prospectively collected whole-genome sequencing and epidemiological data on TB patients. We dissect the ordering of drug resistance mutation acquisition for nine commonly used anti-TB drugs, and we found that the katG S315T mutation first appeared around 1959, followed by rpoB S450L (1969), rpsL L43A (1972), embB M306V (1978), rrs 1401 (1981), fabG1 (1982), pncA (1985) and folC (1988) mutations. GyrA gene mutations appeared after the year of 2000. We observed that the first expansion of Mycobacterium tuberculosis (M.tb) resistance population among eastern China appeared after the introduction of isoniazid, streptomycin and para-amino salicylic acid, and the second expansion after the ethambutol, rifampicin, pyrazinamide, ethionamide and aminoglycosides. We speculate these two expansions are linked with population shift historically. By geospatial analysis, we found drug-resistant isolates migrated within eastern China. With epidemiological data of clonal strains, we observed some strains can evolve continuously in individuals and transmit readily in a population. In conclusion, this study mirrored the emergence and evolution of drug-resistant M.tb in eastern China were linked to the sequence and timing of introduction of anti-TB drugs, and multiple factors may contribute to the resistant population enlarged. To resolve the epidemic of drug-resistant TB, it requires applying anti-TB drugs carefully and/or identifying resistant patients timely to prevent them from developing high-level resistance and transmitting to others.

Implementation of control measures against an outbreak due to Clostridioides difficile producing toxin B in a tertiary hospital in Mexico.

SummaryIntroductionTo describe the outbreak of Clostridioides difficile infection (CDI), and the impact of the prevention and control measures that were implemented in the “Hospital Juárez de México” (HJM) for its control.MethodsA cross-sectional, descriptive, observational, and retrospective study was designed. All information on the hospital outbreak and on health care-associated infections (HCAI) was obtained from the files of the Hospital Epidemiological Surveillance Unit (HESU) of the HJM.ResultsA total of 15 cases of CDI were detected from February 20th to May 22nd, 2018, which represented 55.6% and 44.4% for the male and female gender, respectively, with an average age of 56 years and a range of 24 to 86 years old. It was possible to identify six failures and deficiencies that involved health personnel and hospital logistics through analyses based on the situational diagnosis in the services involved and through the construction of cause-effect diagrams. Additionally, through the detection of the outbreak by means of laboratory tests and timeline, the HESU team implemented measures and prospective surveillance to control and prevent the emergence of new cases.ConclusionsThe implementation of basic quality tools, control measures, and the prospective epidemiological surveillance had a positive impact on the control against the outbreak of C. difficile producing toxin B.

Search and Contain: Impact of an Integrated Genomic and Epidemiological Surveillance and Response Program for Control of Carbapenemase-producing Enterobacterales.

BackgroundMultiresistant organisms (MROs) pose a critical threat to public health. Population-based programs for control of MROs such as carbapenemase-producing Enterobacterales (CPE) have emerged and evaluation is needed. We assessed the feasibility and impact of a statewide CPE surveillance and response program deployed across Victoria, Australia (population 6.5 million).MethodsA prospective multimodal intervention including active screening, carrier isolation, centralized case investigation, and comparative pathogen genomics was implemented. We analyzed trends in CPE incidence and clinical presentation, risk factors, and local transmission over the program’s first 3 years (2016–2018).ResultsCPE case ascertainment increased over the study period to 1.42 cases/100 000 population, linked to increased screening without a concomitant rise in active clinical infections (0.45–0.60 infections/100 000 population, P = .640). KPC-2 infection decreased from 0.29 infections/100 000 population prior to intervention to 0.03 infections/100 000 population in 2018 (P = .003). Comprehensive case investigation identified instances of overseas community acquisition. Median time between isolate referral and genomic and epidemiological assessment for local transmission was 11 days (IQR, 9–14). Prospective surveillance identified numerous small transmission networks (median, 2; range, 1–19 cases), predominantly IMP and KPC, with median pairwise distance of 8 (IQR, 4–13) single nucleotide polymorphisms; low diversity between clusters of the same sequence type suggested genomic cluster definitions alone are insufficient for targeted response.ConclusionsWe demonstrate the value of centralized CPE control programs to increase case ascertainment, resolve risk factors, and identify local transmission through prospective genomic and epidemiological surveillance; methodologies are transferable to low-prevalence settings and MROs globally.

A multi-centre, prospective epidemiological surveillance study considering ophthalmic complications of functional endoscopic sinus surgery.

This prospective, epidemiological British Ophthalmological Surveillance Unit study into ophthalmic complications of functional endoscopic sinus surgery aimed to determine the minimum incidence, presenting features and management throughout the UK. Cases of ophthalmic complications of functional endoscopic sinus surgery, between February 2016 and February 2018, were identified through the British Ophthalmological Surveillance Unit reporting card system. Reporting ophthalmic consultants were sent an initial questionnaire, followed by a second questionnaire at six months. Twenty-six cases of ophthalmic complications of functional endoscopic sinus surgery were reported. The majority (16 cases (62 per cent)) had limitations of ocular motility at presentation. The most common final diagnosis was rectus muscle (33 per cent) and nasolacrimal duct trauma (27 per cent). Using national data, this study reports a minimum incidence of ophthalmic complications of functional endoscopic sinus surgery in the UK of 0.2 per cent over two years. In terms of ophthalmic complications, functional endoscopic sinus surgery is shown to be safe. Ophthalmic complications are rare, but when they do occur, they commonly result in rectus muscle trauma, often requiring surgical intervention.

Characteristics of influenza in elderly patients with and without diabetes, hospitalized for severe acute respiratory infection in a tertiary care hospital from Bucharest Romania - a three-year prospective epidemiological surveillance study.

Patients with diabetes may be at a higher risk of developing complicated influenza. We report the characteristics of influenza in hospitalized elderly patients with and without diabetes, in three consecutive influenza seasons. The study included patients admitted for severe acute respiratory infection (SARI) in the National Institute for Infectious Diseases "Prof. Dr. Matei Balș", Bucharest, during a three-year active epidemiological surveillance study (2015/16, 2016/17, 2017/18), in the I-MOVE+ hospital network. A total of 349 patients were tested by PCR over the duration of the study. The percentage of patients with diabetes was comparable throughout the seasons: 34.7%, 28.3% and 30.4% (p=0.587). Influenza A was the main viral type circulating in 2015/16 and 2016/17 (100% and 97.6%) in our study population, while in 2017/18, B viruses predominated (90.0%). Diabetics presented a higher median number of comorbidities (3 vs. 2) p<0.001, and two-fold higher odds of also associating obesity (OR=2.1, 95%CI:1.3-3.4, p=0.003), compared to those without diabetes. Diabetics also tested positive for influenza more often (p=0.296). Only 6 patients with diabetes (5.4%) from our study had been vaccinated against influenza, and most (n=4) of those who had been vaccinated tested negative for influenza. Our study is the first to describe the circulation of influenza viral types in elderly diabetic patients hospitalized for SARI. The results reinforce the national and international recommendation to vaccinate against influenza all patients with diabetes.

Active Epidemiological Surveillance: the Key for Effective Infection Prevention in Pediatric Surgery

Approaches to the prevention of surgical site infections (SSI) in pediatric surgery is an extrapolation of data obtained mainly from studies in the adult surgical patients. In Russia, data on the actual incidence of SSI in pediatric surgery are almost nonexistent. It is known that one of the reasons for the low effectiveness of SSI prevention is a weak system of epidemiological surveillance, which leads to an underestimation of risk factors and the urgency of the problem. A number of preventive measures aimed at preventing of SSI have shown efficacy in adult surgical patients. One of the leading position belongs to antimicrobial prophylaxis. The study was conducted in St. Petersburg State Children's city hospital № 19 named after K. A. Rauhfus. The data were obtained during a retrospective and prospective epidemiological surveillance among patients of surgical units. It has been shown that SSIs in children have high morbidity. The effectiveness of detecting the real incidence of SSI depends on the methods of epidemiological surveillance: 3.8 per 100 surgeries using standard approaches of surveillance and 11.6 using specially developed forms of active epidemiological surveillance. The incidence of SSI varied depending on the type of surgical unit: 3.8 per 100 surgeries in the traumatology unit, 7.1 in the neurosurgical unit and 15.3 in the general surgery unit. In the etiologic structure, S. aureus predominates (46.5%), E. coli (22.2%) and S. epidermidis (16.7%) were respectively in the second and third positions. It has been shown that antimicrobial prophylaxis is an effective measure for prevention of SSI in pediatric surgery (the odds ratio OR in the case-control study was 0.52 (95% CI = 0.3–0.8)).

EPIDEMIOLOGICAL FEATURES OF BACTERIAL INFECTIONS IN BONE MARROW TRANSPLANT UNITS

The aim of the study was to identify the epidemiological features of bacterial infections in patients and circulation of epidemiologically significant microorganisms in the bone marrow transplant (BMT) units. Materials and methods. The study was conducted in three BMT departments. To identify the epidemiological features of bacterial infections, a prospective observational study was conducted from 01 April 2014 to 31 August 2014 (91 patients) which included active detection of cases of infection and microbiological examination of patients. In order to detect the circulation of epidemiologically significant microorganisms, point prevalence studies (59 patients, 170 environmental samples) were conducted. To study the role of colonization, microbiological monitoring of patients on admission to the department was carried out, and repeated every week before discharge. Swab samples from skin and mucous membrane of the oral cavity and stool sampleswere included in the monitoring. In total, 639 samples from 50 patients were tested. Results. The study revealed a high incidence of infectious complications in BMT patients (100 cases of bacterial infections in 57 patients: sepsis 30.8 per 100 patients, pneumonia 26.4 per 100 patients, urinary tract infections 32.9 per 100 patients, soft tissue infection 9.9 per 100 patients, catheter-associated bloodstream infection 9.9 per 100 patients). Most infections were caused by Gram-negative bacteria, in particular K. pneumoniae. The onset of disease manifestation was preceded by colonization of the patient with these microorganisms. Fatal outcomes were observed from sepsis and pneumonia caused by K. pneumoniae and/or P. aeruginosa. Sepsis and pneumonia were often associated with cytopenia, RR 2.63 [95% CI 1.52–4.57] p = 0.004 and RR 3.97 [95% CI 2.19–7.19] p 0.001 respectively. In course of observation, the frequency of colonization of patients with microorganisms susceptible to antibiotics decreased, and colonization with resistant pathogens increased. A series of prevalence studies revealed a constant circulation of VRE in the BMT units with a contacttransmission via household objects. Multidrug-resistant gram-negative microorganisms did not have a constant circulation and appeared sporadically against the background of the constant circulation of susceptible strains of these pathogens. Conclusions. Prospective epidemiological surveillance and microbiological monitoring are required in the BMT units. Widespread contamination of household objects in the environment indicates the need to strengthen the hygienic education of patients and visitors as well as disinfection of these facilities. In addition, we recommend introduction of weekly fecal screening cultures to monitor intestinal colonization of patients with MDRO.

Toward Electronic Surveillance of Invasive Mold Diseases in Hematology-Oncology Patients: An Expert System Combining Natural Language Processing of Chest Computed Tomography Reports, Microbiology, and Antifungal Drug Data.

Prospective epidemiologic surveillance of invasive mold disease (IMD) in hematology patients is hampered by the absence of a reliable laboratory prompt. This study develops an expert system for electronic surveillance of IMD that combines probabilities using natural language processing (NLP) of computed tomography (CT) reports with microbiology and antifungal drug data to improve prediction of IMD. Microbiology indicators and antifungal drug-dispensing data were extracted from hospital information systems at three tertiary hospitals for 123 hematology-oncology patients. Of this group, 64 case patients had 26 probable/proven IMD according to international definitions, and 59 patients were uninfected controls. Derived probabilities from NLP combined with medical expertise identified patients at high likelihood of IMD, with remaining patients processed by a machine-learning classifier trained on all available features. Compared with the baseline text classifier, the expert system that incorporated the best performing algorithm (naïve Bayes) improved specificity from 50.8% (95% CI, 37.5% to 64.1%) to 74.6% (95% CI, 61.6% to 85.0%), reducing false positives by 48% from 29 to 15; improved sensitivity slightly from 96.9% (95% CI, 89.2% to 99.6%) to 98.4% (95% CI, 91.6% to 100%); and improved receiver operating characteristic area from 73.9% (95% CI, 67.1% to 80.6%) to 92.8% (95% CI, 88% to 97.5%). An expert system that uses multiple sources of data (CT reports, microbiology, antifungal drug dispensing) is a promising approach to continuous prospective surveillance of IMD in the hospital, and demonstrates reduced false notifications (positives) compared with NLP of CT reports alone. Our expert system could provide decision support for IMD surveillance, which is critical to antifungal stewardship and improving supportive care in cancer.

Prospective Whole-Genome Sequencing Enhances National Surveillance of Listeria monocytogenes.

Whole-genome sequencing (WGS) has emerged as a powerful tool for comparing bacterial isolates in outbreak detection and investigation. Here we demonstrate that WGS performed prospectively for national epidemiologic surveillance of Listeria monocytogenes has the capacity to be superior to our current approaches using pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), multilocus variable-number tandem-repeat analysis (MLVA), binary typing, and serotyping. Initially 423 L. monocytogenes isolates underwent WGS, and comparisons uncovered a diverse genetic population structure derived from three distinct lineages. MLST, binary typing, and serotyping results inferred in silico from the WGS data were highly concordant (>99%) with laboratory typing performed in parallel. However, WGS was able to identify distinct nested clusters within groups of isolates that were otherwise indistinguishable using our current typing methods. Routine WGS was then used for prospective epidemiologic surveillance on a further 97 L. monocytogenes isolates over a 12-month period, which provided a greater level of discrimination than that of conventional typing for inferring linkage to point source outbreaks. A risk-based alert system based on WGS similarity was used to inform epidemiologists required to act on the data. Our experience shows that WGS can be adopted for prospective L. monocytogenes surveillance and investigated for other pathogens relevant to public health.

Healthcare-associated infections in a Tunisian university hospital: from analysis to action.

IntroductionOur study was conducted, in university hospital center (UHC) Farhat Hached of Sousse (city in Tunisian center-east), within healthcare-associated infections (HAI) epidemiological surveillance (ES) program, based, among others, on HAI regular prevalence surveys. Our objectives are to resituate HAI prevalence rate and to identify their risk factors (RF) in order to adjust, in our hospital, prevention programs.MethodsIt is a transversal descriptive study, including all patients who had been hospitalized for at least 48 hours, measuring prevalence of HAI a “given day”, with only one passage by service. Risk factors were determined using Epiinfo 6.0, by uni-varied analysis, then, logistic regression stepwise descending for the variables whose pResultsThe study focused on 312 patients. Infected patients prevalence was 12.5% and that of HAI was 14.5%. Infections on peripheral venous catheter (PVC) dominated (42.2%) among all HAI identified. HAI significant RF were neutropenia (p < 10−4) for intrinsic factors, and PVC for extrinsic factors (p = 0,003).ConclusionPredominance of infections on PVC should be subject of specific prevention actions, including retro-information strategy, prospective ES, professional practices evaluation and finally training and increasing awareness of health personnel with hygiene measures. Finally, development of a patient safety culture with personnel ensures best adherence to hygiene measures and HAI prevention.

Shoulder Injuries Among US High School Athletes, 2005/2006–2011/2012

The objective of this study was to describe shoulder injuries in a nationally representative sample of high school athletes playing 9 sports. A national estimate of shoulder injuries among high school athletes was subsequently calculated. Injury data were collected in 9 sports (boys' football, soccer, basketball, wrestling, and baseball; girls' soccer, volleyball, basketball, and softball) during the 2005-2006 through 2011-2012 academic years from a nationally representative sample of high schools via High School Reporting Information Online. During the 2005-2006 through 2011-2012 academic years, high school athletes in this study sustained 2798 shoulder injuries during 13,002,321 athlete exposures, for an injury rate of 2.15 per 10,000 athlete exposures. This corresponds to a nationally estimated 820,691 injuries during this time period. Rates of injury were higher in competition as compared with practice (rate ratio = 3.17 [95% confidence interval: 2.94-3.41]). The highest rate of injury was in football (4.86) and the lowest in girls' soccer (0.42). The most common types of injury were strain/sprain (37.9%) and dislocation/separation (29.2%). Boys were more likely than girls to sustain their injuries after contact with another person or with the playing surface. Surgical repair was required for 7.9% of the injuries. Time loss from athletic participation varied among sports, with 40.7% of athletes returning within 1 week, whereas 8.2% were medically disqualified for their season/career. High school shoulder injury rates and patterns varied by sport and gender. Prospective epidemiologic surveillance is warranted to discern trends and patterns to develop evidence-based interventions to prevent shoulder injuries.

P. aeruginosa bloodstream infections among hematological patients: an old or new question?

Pseudomonas aeruginosa is a well-known cause of severe and potentially life-threatening infections among hematological patients. A prospective epidemiological surveillance program ongoing at our Hematology Unit revealed an increase over time of P. aeruginosa bloodstream infections (BSI). Their impact on outcome and antibiotic susceptibility was analyzed. BSI which consecutively occurred at our institution during a 70-month period were evaluated and correlated with type of pathogen, status of underlying disease, neutropenia, previous antibiotic therapy, resistance to antibiotics, and outcome. During the observation period, 441 BSI were recorded. Frequency of Gram-negative BSI was higher than that of other pathogens (57.3%). Overall, 66 P. aeruginosa BSI were recorded; 22 out of 66 were multiresistant (MR P. aeruginosa). Thirty-day mortality for all BSI was 11.3%; it was 27.3% for P. aeruginosa BSI and 36.4% for MR P. aeruginosa. At multivariate analysis, only active hematological disease and P. aeruginosa BSI were associated to an increased risk of death. For MR P. aeruginosa, BSI mortality was 83.3% vs. 18.8% when empiric therapy included or not an antibiotic with in vitro activity against P. aeruginosa (p=0.011). Together with active disease, the emergence of P. aeruginosa BSI, particularly if multiresistant, was responsible for an increased risk of death among hematological patients at our institution. In this scenario, reconsidering the type of combination antibiotic therapy to be used as empiric treatment of neutropenic fever was worthwhile.

Prospective epidemiologic surveillance of invasive pneumococcal disease and pneumonia in children in San José, Costa Rica

Streptococcus pneumoniae (SP) is the leading cause of vaccine-preventable death in children <5 years of age, globally. This surveillance determined incidence rates of invasive pneumococcal disease (IPD), clinical and chest radiograph-confirmed pneumonia (CXR+Pn); and SP serotype distribution and antimicrobial susceptibility in children in San José, Costa Rica. This was a 2-year prospective, population-based surveillance conducted in 2007-2009 in children aged 28 days to 36 months presenting to participating healthcare centers. Eligibility criteria for study inclusion were as follows: temperature ≥ 39.0°C within 24h and/or clinical suspicion of IPD or pneumonia. 8801 subjects were enrolled. Median age: 14.5 months. A total of 25 children had invasive pneumococcal disease with S. pneumoniae isolated from nonduplicative cultures (22) or detected solely by PCR and a clinical picture consistent with IPD (3). Sources of positive cultures (some children had >1 positive culture) were: blood (20), pleural fluid (4), and cerebrospinal fluid (3). Of the 3 cases detected solely by PCR, 2 were from cerebrospinal fluid and 1 from pleural fluid. The overall IPD incidence rates for culture-positive only cases for children aged 28 days to <3 years was 33.7/100,000 per year for years 1 and 2 combined. Age stratification of culture-positive only subjects showed a peak during year 1 (106.8/100,000) in children 28 days to <6 months of age group, and in year 2 (45.5/100,000) in children 12 months to <24 months of age group. Most common serotypes were 14 (28.6%), followed by 3, 4, 6A, 19A, and 22F (9.5% each). Of 22 nonduplicative IPD isolates, 42.9% were penicillin- and trimethoprim/sulfamethoxazole nonsusceptible isolates. Consideration of PCR-positive cases increases the incidence of IPD for children aged 28 days to <3 years to 46.0/100,000. Overall incidence of clinical pneumonia and CXR+Pn was 1968/100,000 and 551/100,000, respectively. There is a considerable burden of IPD and pneumonia in children in San José. These epidemiologic data serve as a baseline to evaluate the effectiveness of the incorporation of new conjugate pneumococcal vaccines into the National Immunization Program in Costa Rican children.

Impact of influenza infection on children's hospital admissions during two seasons in Athens, Greece

A prospective epidemiologic surveillance of hospitalizations associated with influenza was conducted in order to calculate population-based hospitalization rates. Eligible children were 6 months to 13 years of age and were admitted to one of the two large children's hospitals in the Athens area during two influenza seasons. Nasopharyngeal aspirates were tested for influenza by a polymerase reaction assay. Influenza accounted for 9.9–11.8% of all admissions during the influenza season and the overall annual rate of hospitalizations was 13.6–16.8 cases per 10,000 children being highest for children under 5 years of age (26–31.2/10,000 children). Febrile seizures and acute otitis media were the two most common complications associated with influenza and antibiotics were administered to 61% of flu positive patients. Influenza is associated with high hospitalization rates among young children and these may be substantially reduced with the introduction of routine immunization.

PIV-13 Prospective respiratory epidemiologic surveillance study (press) – viral respiratory infections in a long-term care facility (LTCF) population

Providencia stuartii survives well in natural environment and often causes opportunistic infection in residents of long-term care facilities (LTCFs). Clinical isolates of P. stuartii are usually resistant to multiple antibiotics. The bacterium is also naturally resistant to colistin and tigecycline. Treatment of infections caused by carbapenem-resistant P. stuartii is challenging.During a 15-month period in 2013–2014, four isolates (P1, P2, and P3B/P3U) of P. stuartii showing intermediate resistance to imipenem were identified at a regional hospital in southern Taiwan. They were identified from three patients (P1–P3) transferred from the same LTCF for the treatment of the infection. Pulsed-field gel electrophoresis was used to genotype the isolates. Resistance genes/plasmids and outer membrane proteins were investigated by polymerase chain reaction and sequence analysis.Isolates P1 and P3B/P3U demonstrated similar pulsotypes. All isolates were found to have resistance genes (blaCMY-2, qnrD1, aac(6′)-Ib-cr) carried on nonconjugative IncA/C plasmids of different sizes. A single point mutation was identified in the chromosomal gyrA (Ser83Ile) and parC (Ser84Ile) genes of all isolates. Various point mutations and insertion/deletion changes were found in their major outer membrane protein gene ompPst1.Isolates of similar pulsotypes could appear after 15 months and caused urosepsis in another resident of the same LTCF. The bacterium may have persisted in the environment and caused opportunistic infection. As LTCF residents are usually vulnerable to infections, surveillance of multidrug-resistant organisms and infection control intervention that have been established in acute-care hospitals to control infections by resistant organisms are apparently as essential in LTCFs.

Genetic drift of norovirus genotype GII-4 in seven consecutive epidemic seasons in Hungary

Background Noroviruses are common pathogens in human gastroenteritis outbreaks worldwide. They belong to a genetically diverse group of RNA viruses with multiple genogroups (G) and genotypes. Genotype GII-4 norovirus (Lordsdale) is the predominant agent in epidemics. Objectives To investigate the genetic variation in GII-4 strains isolated during seven epidemic seasons in Hungary from November 2000 to June 2007. Study design Using the prospective epidemiological surveillance of norovirus outbreaks in Hungary, GII-4 strains were selected for further genetic analysis. After phylogenetic analysis, RNA-polymerase (open reading frame 1; ORF1), capsid (ORF2) and the ORF1/ORF2 junction were analysed by RT-PCR and sequencing. Results Three hundred and seventy-seven (76.8%) of 491 confirmed norovirus outbreaks were caused by genotype GII-4. GII-4 was the predominant genotype in six of the seven epidemic seasons. Four main GII-4 variants – epidemic point mutants – (GII-4-2000, GII-4-2002, GII-4-2004 and GII-4-2006b) were detected, with each variant predominating in two consecutive epidemic seasons. Conclusions Genotype GII-4 was confirmed as the predominant genetic type in epidemic norovirus seasons in Hungary. Genetic drift successfully promotes the re-emergence of GII-4 variants in the population. The elevated number of norovirus outbreaks in the population predicts the emergence of new GII-4 genetic variants as part of an international epidemic.

Lactococcus garvieae infections in humans: possible association with aquaculture outbreaks

Lactococcus garvieae is an important pathogen in aquaculture, outbreaks of which significantly affect production. It is a rare pathogen with a low virulence in human infection. The relation between the aquaculture outbreak and the human infection has not been clarified. Prospective and retrospective epidemiologic surveillance of the four patients with L. garvieae infection between 2000 and 2003 and their relations to the aquaculture outbreaks of L. garvieae were conducted. All the four patients with L. garvieae infection were associated with gastrointestinal disorders. Three of the four patients gave a history of consuming raw fish and in three of the four patients, the infection occurred in summer between June and August while there is a decrease of fisheries production and an increase in L. garvieae infection in aquaculture farms. There was a 100% identity of 16S rDNA sequence of L. garvieae isolates from patient 1 and from the squid muscle obtained from the restaurant where patient 1 consumed the raw fish. Sporadic occurrence of L. garvieae infection in human appears to correlate with the seasonal aquaculture outbreaks of L. garvieae infection. The presence of gastro-intestinal disorder may facilitate L. garvieae infection.

Exposición a dispositivos extrínsecos, un indicador de infección intrahospitalaria

Objective To design a protocol for the systematic surveillance of nosocomial infections associated with the devices most frequently used in pediatric intensive care units (PICUs). Material and methods We performed a prospective epidemiological surveillance study of nosocomial infections associated with devices such as central venous catheters, mechanical ventilation and urinary catheters in a PICU from April to June 2004. The criteria of the Centers for Disease Control and Prevention (CDC) were used to define bacteremia, pneumonia, and urinary tract infection. Results A total of 326 pediatric patients were studied (45% with urinary catheters, 30% with venous catheters, and 25% under mechanical ventilation). The nosocomial infection rate was 0.6 cases of bacteremia, 0.4 cases of pneumonia and 0.3 cases of urinary tract infection per 100 device days. Conclusions Epidemiological surveillance of nosocomial infections using a simple protocol allows risk factor-associated infection rates to be determined in a specific time period and measures for infection control to be implemented. These strategies aim to reduce the frequency of infections and consequent cost per days of hospital stay.

Molecular Epidemiology of EndemicClostridium difficileInfection and the Significance of Subtypes of the United Kingdom Epidemic Strain (PCR Ribotype 1)

We previously identified two subtypes of the epidemic strain Clostridium difficile PCR ribotype 1, one clindamycin-sensitive strain (arbitrarily primed PCR [AP-PCR] type Ia) and a closely related clindamycin-resistant strain (AP-PCR type Ib) in our institution. We have now carried out prospective epidemiological surveillance for 4 years, immediately following the relocation of two acute medicine wards for elderly patients (wards A and B), to determine the clinical epidemiology of subtypes of the epidemic C. difficile PCR ribotype 1 group. To maximize the chance of strain discrimination, we used three DNA fingerprinting methods, AP-PCR, ribospacer PCR (RS-PCR), and pulsed-field gel electrophoresis (PFGE), to analyze C. difficile isolates recovered from symptomatic patients and from repeated environmental samplings. On ward B the incidence of C. difficile infection correlated significantly with the prevalence of environmental C. difficile both in ward areas closely associated with patients and health care personnel (r = 0.53; P < 0.05) and in high-reach sites (r = 0.85; P < 0.05). No such relationships were found on ward A. Seventeen distinct C. difficile genotypes were identified, 17 by AP-PCR, 12 by PFGE, and 11 by RS-PCR, but only 4 of 17 genotypes caused patient infection. Isolates recovered from the hospital ward environment were much more diverse (14 genotypes). AP-PCR type Ia represented >90% of the C. difficile isolates. In addition to this genotype, only two others were isolated from both patient feces and environmental surfaces. AP-PCR type Ib (clindamycin-resistant PCR ribotype 1 clone) was not associated with any cases of C. difficile infection and was isolated from the environment on only two occasions, after having been implicated in a cluster of six C. difficile infections 5 months before this study. The disappearance of this strain implies that differences in virulence and/or selective pressures may exist for this strain and the closely related, widespread C. difficile AP-PCR type Ia strain. Our findings emphasize the need to understand the epidemiology and virulence of clinically significant strains to determine successful control measures for C. difficile infections.